河南甄坟沟大桥支座更换布置方案研究

Research on Bearing Replacement Layout of Zhenfengou Bridge in He'nan

以支座损坏后进行全部更换的河南甄坟沟大桥为研究对象,利用有限元软件MIDAS/civil,对具有较大纵坡和较高桥墩的四跨先简支后连续分体式组合小箱梁桥的静动力特性进行计算。分析比选了两种支座更换布置方案:对称的2号墩固定支座方案和非对称的3号墩固定支座方案。根据该桥梁静力计算、自振特性计算和在设计地震作用下的反应谱分析计算,得出3号墩固定支座方案为支座更换合理布置方案的结论。

The Zhenfengou Bridge in He＇nan, which is bearing replacements after damaging, was taken as the object to study in this paper. The finite element software MIDAS/civil was applied to set up the spatial model, in which the characteristics of the great longitudinal slop and the high piers were considered, so the static and dynamic properties of this simply supported to continuous four spans separated box girder bridge were calculated. Two bearing replacement programs were compared after analysis, including the symmetric fixed support program on the 2nd pier and the non-symmetric fixed support program on the 3rd pier. According to static calculation results, the structural dynamical characteristics and the response spectrum analysis results support to the design earthquake, it is obtained that the reasonable bearing replacement program is the 3rd pier fixed support program.